[v1] scripts: headers_install.sh: Normalize __ASSEMBLY__ to __ASSEMBLER__

[PATCH] scripts: headers_install.sh: Normalize __ASSEMBLY__ to __ASSEMBLER__

Posted by Thomas Huth 4 days, 16 hours ago

From: Thomas Huth <thuth@redhat.com>

A previous patch to headers_install.sh normalized the usage of
__ASSEMBLER__ to __ASSEMBLY__ in the UAPI headers due to the
assumption that older versions of GCC might not define __ASSEMBLER__
automatically and thus using __ASSEMBLER__ in the UAPI headers might
break compilation with very old versions of GCC. However, as we now
reassured, even GCC 2.95 still defines __ASSEMBLER__ automatically
(and even older versions are hopefully not in use with the current
Linux UAPI headers anymore).
__ASSEMBLER__ is also set automatically by other C compilers like PCC
(see https://github.com/IanHarvey/pcc/blob/cvs2git/2018.09.20/cc/cc/cc.1#L405)
and Tiny-C (see https://repo.or.cz/tinycc.git/commitdiff/a25325e9be13e52a),
so using __ASSEMBLER__ in UAPI header files should really be fine.

Thus let's head forwards and standardize on __ASSEMBLER__ instead
of __ASSEMBLY__ in the UAPI header files now.

Suggested-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/all/2030a963-33bc-43fe-9a2b-9c626d7d8360@redhat.com/
Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 Based-on: https://lore.kernel.org/all/20260630-uapi-assembly-v2-1-8e7bee2fe816@weissschuh.net/

 To avoid the churn, feel free to squash this patch with
 Thomas Weißschuh's original patch as long as it has not been
 merged to Linus' tree yet.

 scripts/headers_install.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/headers_install.sh b/scripts/headers_install.sh
index 83e4475968781..2f1d1767ca267 100755
--- a/scripts/headers_install.sh
+++ b/scripts/headers_install.sh
@@ -36,7 +36,7 @@ sed -E -e '
 	s/(^|[^a-zA-Z0-9])__packed([^a-zA-Z0-9_]|$)/\1__attribute__((packed))\2/g
 	s/(^|[[:space:](])(inline|asm|volatile)([[:space:](]|$)/\1__\2__\3/g
 	s@#(ifndef|define|endif[[:space:]]*/[*])[[:space:]]*_UAPI@#\1 @
-	s/__ASSEMBLER__/__ASSEMBLY__/g
+	s/__ASSEMBLY__/__ASSEMBLER__/g
 ' $INFILE > $TMPFILE || exit 1
 
 scripts/unifdef -U__KERNEL__ -D__EXPORTED_HEADERS__ $TMPFILE > $OUTFILE
-- 
2.55.0

Re: [PATCH] scripts: headers_install.sh: Normalize __ASSEMBLY__ to __ASSEMBLER__

Posted by Thomas Weißschuh 3 days, 4 hours ago

On 2026-07-20 12:10:25+0200, Thomas Huth wrote:
> From: Thomas Huth <thuth@redhat.com>
> 
> A previous patch to headers_install.sh normalized the usage of
> __ASSEMBLER__ to __ASSEMBLY__ in the UAPI headers due to the
> assumption that older versions of GCC might not define __ASSEMBLER__
> automatically and thus using __ASSEMBLER__ in the UAPI headers might
> break compilation with very old versions of GCC. However, as we now
> reassured, even GCC 2.95 still defines __ASSEMBLER__ automatically
> (and even older versions are hopefully not in use with the current
> Linux UAPI headers anymore).
> __ASSEMBLER__ is also set automatically by other C compilers like PCC
> (see https://github.com/IanHarvey/pcc/blob/cvs2git/2018.09.20/cc/cc/cc.1#L405)
> and Tiny-C (see https://repo.or.cz/tinycc.git/commitdiff/a25325e9be13e52a),
> so using __ASSEMBLER__ in UAPI header files should really be fine.

I am not that happy about this explanation. The note about old GCC was
dropped in the committed version of the patch.
It should be enough to just explain why __ASSEMBLER__ is better.

> Thus let's head forwards and standardize on __ASSEMBLER__ instead
> of __ASSEMBLY__ in the UAPI header files now.
> 
> Suggested-by: Thomas Weißschuh <linux@weissschuh.net>
> Link: https://lore.kernel.org/all/2030a963-33bc-43fe-9a2b-9c626d7d8360@redhat.com/
> Signed-off-by: Thomas Huth <thuth@redhat.com>
> ---
>  Based-on: https://lore.kernel.org/all/20260630-uapi-assembly-v2-1-8e7bee2fe816@weissschuh.net/
> 
>  To avoid the churn, feel free to squash this patch with
>  Thomas Weißschuh's original patch as long as it has not been
>  merged to Linus' tree yet.
> 
>  scripts/headers_install.sh | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/scripts/headers_install.sh b/scripts/headers_install.sh
> index 83e4475968781..2f1d1767ca267 100755
> --- a/scripts/headers_install.sh
> +++ b/scripts/headers_install.sh
> @@ -36,7 +36,7 @@ sed -E -e '
>  	s/(^|[^a-zA-Z0-9])__packed([^a-zA-Z0-9_]|$)/\1__attribute__((packed))\2/g
>  	s/(^|[[:space:](])(inline|asm|volatile)([[:space:](]|$)/\1__\2__\3/g
>  	s@#(ifndef|define|endif[[:space:]]*/[*])[[:space:]]*_UAPI@#\1 @
> -	s/__ASSEMBLER__/__ASSEMBLY__/g
> +	s/__ASSEMBLY__/__ASSEMBLER__/g
>  ' $INFILE > $TMPFILE || exit 1
>  
>  scripts/unifdef -U__KERNEL__ -D__EXPORTED_HEADERS__ $TMPFILE > $OUTFILE
> -- 
> 2.55.0
>

Re: [PATCH] scripts: headers_install.sh: Normalize __ASSEMBLY__ to __ASSEMBLER__

Posted by Thomas Huth 2 days, 18 hours ago

On 21/07/2026 23.32, Thomas Weißschuh wrote:
> On 2026-07-20 12:10:25+0200, Thomas Huth wrote:
>> From: Thomas Huth <thuth@redhat.com>
>>
>> A previous patch to headers_install.sh normalized the usage of
>> __ASSEMBLER__ to __ASSEMBLY__ in the UAPI headers due to the
>> assumption that older versions of GCC might not define __ASSEMBLER__
>> automatically and thus using __ASSEMBLER__ in the UAPI headers might
>> break compilation with very old versions of GCC. However, as we now
>> reassured, even GCC 2.95 still defines __ASSEMBLER__ automatically
>> (and even older versions are hopefully not in use with the current
>> Linux UAPI headers anymore).
>> __ASSEMBLER__ is also set automatically by other C compilers like PCC
>> (see https://github.com/IanHarvey/pcc/blob/cvs2git/2018.09.20/cc/cc/cc.1#L405)
>> and Tiny-C (see https://repo.or.cz/tinycc.git/commitdiff/a25325e9be13e52a),
>> so using __ASSEMBLER__ in UAPI header files should really be fine.
> 
> I am not that happy about this explanation. The note about old GCC was
> dropped in the committed version of the patch.
> It should be enough to just explain why __ASSEMBLER__ is better.
Ok, I sent a v2 with an updated patch description, I hope that's better:

  https://lore.kernel.org/lkml/20260722072928.24500-1-thuth@redhat.com/

If not, please provide a suggestion how it should look like.

  Thanks,
   Thomas

PS: Nicolas, I kept your Reviewed-by in v2 ... if you disagree with the 
updated patch description, please complain there!

Re: [PATCH] scripts: headers_install.sh: Normalize __ASSEMBLY__ to __ASSEMBLER__

Posted by Nicolas Schier 3 days, 14 hours ago

> A previous patch to headers_install.sh normalized the usage of
> __ASSEMBLER__ to __ASSEMBLY__ in the UAPI headers due to the
> assumption that older versions of GCC might not define __ASSEMBLER__
> automatically and thus using __ASSEMBLER__ in the UAPI headers might
> break compilation with very old versions of GCC. However, as we now
> reassured, even GCC 2.95 still defines __ASSEMBLER__ automatically
> (and even older versions are hopefully not in use with the current
> Linux UAPI headers anymore).
> __ASSEMBLER__ is also set automatically by other C compilers like PCC
> (see https://github.com/IanHarvey/pcc/blob/cvs2git/2018.09.20/cc/cc/cc.1#L405)
> and Tiny-C (see https://repo.or.cz/tinycc.git/commitdiff/a25325e9be13e52a),
> so using __ASSEMBLER__ in UAPI header files should really be fine.
> 
> Thus let's head forwards and standardize on __ASSEMBLER__ instead
> of __ASSEMBLY__ in the UAPI header files now.
> 
> Suggested-by: Thomas Weißschuh <linux@weissschuh.net>
> Link: https://lore.kernel.org/all/2030a963-33bc-43fe-9a2b-9c626d7d8360@redhat.com/
> Signed-off-by: Thomas Huth <thuth@redhat.com>
>
> diff --git a/scripts/headers_install.sh b/scripts/headers_install.sh
> index 83e447596878..2f1d1767ca26 100755
> --- a/scripts/headers_install.sh
> +++ b/scripts/headers_install.sh
> @@ -36,7 +36,7 @@ sed -E -e '
>  	s/(^|[^a-zA-Z0-9])__packed([^a-zA-Z0-9_]|$)/\1__attribute__((packed))\2/g
>  	s/(^|[[:space:](])(inline|asm|volatile)([[:space:](]|$)/\1__\2__\3/g
>  	s@#(ifndef|define|endif[[:space:]]*/[*])[[:space:]]*_UAPI@#\1 @
> -	s/__ASSEMBLER__/__ASSEMBLY__/g
> +	s/__ASSEMBLY__/__ASSEMBLER__/g
>  ' $INFILE > $TMPFILE || exit 1
>  
>  scripts/unifdef -U__KERNEL__ -D__EXPORTED_HEADERS__ $TMPFILE > $OUTFILE

Thanks!

Reviewed-by: Nicolas Schier <n.schier@fritz.com>
Tested-by: Nicolas Schier <n.schier@fritz.com>


Even though squashing both commits sounds good to me on the first hand,
I don't want to do that right now, to simplify a possible revert in case
of reported regressions.

-- 
Nicolas

Re: [PATCH] scripts: headers_install.sh: Normalize __ASSEMBLY__ to __ASSEMBLER__

Posted by Nathan Chancellor 3 days, 5 hours ago

On Tue, Jul 21, 2026 at 01:14:55PM +0200, Nicolas Schier wrote:
> > A previous patch to headers_install.sh normalized the usage of
> > __ASSEMBLER__ to __ASSEMBLY__ in the UAPI headers due to the
> > assumption that older versions of GCC might not define __ASSEMBLER__
> > automatically and thus using __ASSEMBLER__ in the UAPI headers might
> > break compilation with very old versions of GCC. However, as we now
> > reassured, even GCC 2.95 still defines __ASSEMBLER__ automatically
> > (and even older versions are hopefully not in use with the current
> > Linux UAPI headers anymore).
> > __ASSEMBLER__ is also set automatically by other C compilers like PCC
> > (see https://github.com/IanHarvey/pcc/blob/cvs2git/2018.09.20/cc/cc/cc.1#L405)
> > and Tiny-C (see https://repo.or.cz/tinycc.git/commitdiff/a25325e9be13e52a),
> > so using __ASSEMBLER__ in UAPI header files should really be fine.
> > 
> > Thus let's head forwards and standardize on __ASSEMBLER__ instead
> > of __ASSEMBLY__ in the UAPI header files now.
> > 
> > Suggested-by: Thomas Weißschuh <linux@weissschuh.net>
> > Link: https://lore.kernel.org/all/2030a963-33bc-43fe-9a2b-9c626d7d8360@redhat.com/
> > Signed-off-by: Thomas Huth <thuth@redhat.com>
> >
> > diff --git a/scripts/headers_install.sh b/scripts/headers_install.sh
> > index 83e447596878..2f1d1767ca26 100755
> > --- a/scripts/headers_install.sh
> > +++ b/scripts/headers_install.sh
> > @@ -36,7 +36,7 @@ sed -E -e '
> >  	s/(^|[^a-zA-Z0-9])__packed([^a-zA-Z0-9_]|$)/\1__attribute__((packed))\2/g
> >  	s/(^|[[:space:](])(inline|asm|volatile)([[:space:](]|$)/\1__\2__\3/g
> >  	s@#(ifndef|define|endif[[:space:]]*/[*])[[:space:]]*_UAPI@#\1 @
> > -	s/__ASSEMBLER__/__ASSEMBLY__/g
> > +	s/__ASSEMBLY__/__ASSEMBLER__/g
> >  ' $INFILE > $TMPFILE || exit 1
> >  
> >  scripts/unifdef -U__KERNEL__ -D__EXPORTED_HEADERS__ $TMPFILE > $OUTFILE
> 
> Thanks!
> 
> Reviewed-by: Nicolas Schier <n.schier@fritz.com>
> Tested-by: Nicolas Schier <n.schier@fritz.com>
> 
> Even though squashing both commits sounds good to me on the first hand,
> I don't want to do that right now, to simplify a possible revert in case
> of reported regressions.

Given the additional information provided in this commit message, I
think it is fine to keep them separate, even aside from the regressions
concern.

-- 
Cheers,
Nathan